U.S. patent number 5,791,044 [Application Number 08/720,413] was granted by the patent office on 1998-08-11 for assembly and method for catalytic converter structures.
This patent grant is currently assigned to Engelhard Corporation. Invention is credited to Boris Y. Brodsky, Gordon W. Brunson, William A. Whittenberger.
United States Patent |
5,791,044 |
Whittenberger , et
al. |
August 11, 1998 |
Assembly and method for catalytic converter structures
Abstract
A metal foil leaf assembly for catalytic converters, the leaf
assembly including at least two juxtaposed foil leaves, each having
opposite ends to establish a leaf length and at least one
corrugated leaf segment shorter than the leaf length. At least one
of the opposite ends is joined by appropriate technique, such as
welding, brazing, or folding. The leaf assembly is incorporated in
catalytic converter body having a cylindrical jacket tube. A
plurality of radiating foil leaves extend in adjacent curved paths
and are joined at the outer ends thereof to the jacket tube. The
foil leaves define fluid passage cells between juxtaposed flat and
corrugated leaf segments, and each of the foil leaves has at least
one corrugated segment.
Inventors: |
Whittenberger; William A.
(Leavittsburg, OH), Brunson; Gordon W. (Chagrin Falls,
OH), Brodsky; Boris Y. (Mayfield Heights, OH) |
Assignee: |
Engelhard Corporation (Iselin,
NJ)
|
Family
ID: |
24309471 |
Appl.
No.: |
08/720,413 |
Filed: |
September 30, 1996 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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557617 |
Dec 22, 1995 |
|
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Current U.S.
Class: |
29/890; 422/177;
422/180; 428/592; 502/439; 502/527.22; 502/527.24 |
Current CPC
Class: |
B01J
35/04 (20130101); F01N 3/281 (20130101); F01N
3/2814 (20130101); F01N 13/017 (20140601); Y10T
29/49345 (20150115); F01N 2470/24 (20130101); Y10T
428/12333 (20150115); F01N 2330/04 (20130101) |
Current International
Class: |
B01J
35/04 (20060101); B01J 35/00 (20060101); F01N
3/28 (20060101); F01N 7/00 (20060101); F01N
7/04 (20060101); B21D 011/06 () |
Field of
Search: |
;422/171,177,180,211,222
;502/439,527,527.22,527.24 ;29/890 ;60/299
;428/116,593,594,592,603,287 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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322566 |
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Jul 1989 |
|
EP |
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613997 |
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Sep 1994 |
|
EP |
|
Primary Examiner: Tran; Hien
Parent Case Text
This is a division of application Ser. No. 08/577,617, filed Dec.
22, 1995.
Claims
What is claimed is:
1. A method for making a catalyst support body for a catalytic
converter comprising:
forming an elongated strip of metal foil having a series of
alternating flat and corrugated segments along the length of the
strip and transverse bands of flat metal foil between at least some
of said flat and corrugated segments, wherein said flat and
corrugated segments are coated with a catalyst and the transverse
bands of flat metal foil are not coated with a catalyst;
folding the strip along at least one transverse band to provide a
plurality of adjacent foil leaf elements having two opposite ends
said foil leaf elements having at least one flat catalyst coated
segment and at least one corrugated catalyst coated segment along
the length of the foil elements, at least one end of the foil leaf
elements having a flat metal foil region which is not coated with a
catalyst;
assembling a plurality of the adjacent foil leaf elements to form a
catalyst support body having a central region and a periphery, said
foil leaf elements being assembled to radiate in adjacent curved
paths such that one end of the foil leaf elements extend outwardly
to the periphery of the body and the opposite end of the foil leaf
elements extend into the central region of the body, the flat and
corrugated segments of the foil leaf elements defining fluid
passage cells between alternating flat and corrugated segments of
adjacent foil leaf elements.
2. A method of making a catalyst support body for a catalytic
converter comprising
forming an elongated metal foil strip with two opposite ends, the
strip having a series of longitudinal foil cycles between opposite
ends of the strips, each cycle including alternating flat and
corrugated segments coated with catalyst and transverse bands of
flat metal foil having no catalyst coating located at the beginning
and end of each cycle;
folding the strip along at least one transverse band of a cycle to
provide a stack of interconnected metal foil layers having
alternating flat and corrugated catalyst coated segments along the
length of the metal foil layers, the stack of interconnected metal
foil layers having two ends, both ends of the strip terminating on
the same end of the stack;
arranging the stack of interconnected metal foil layers to provide
a plurality of interconnected foil layers shaped into a star
configuration wherein the ends of the folded strip meet to complete
the configuration;
joining the ends of the strip; and
assembling the star configured foil layers into a honeycomb body
having a central region, the foil layers extending outwardly in
radiating curved paths from the central region of the honeycomb
body, the foil layers having flat and corrugated segments along
their length, the flat and corrugated segments of the foil layers
defining fluid passage cells between alternating corrugated and
flat segments of adjacent foil layers.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
The present application is related to U.S. application Ser. No.
08/501,755, filed Jul. 12, 1995 by David T. Sheller and William A.
Whittenberger, and to concurrently filed U.S. applications,
entitled Assembly and Method for Making Catalytic Converter
Structures, as follows: Ser. No. 08/577,616 by William A.
Whittenberger, John J. Chlebus, Joseph E. Kubsh, and Boris Y.
Brodsky; Ser. No. 08/580,101 by David T. Sheller and William A.
Whittenberger; Ser. No. 08/577,618 by William A. Whittenberger and
Boris Y. Brodsky; Ser. No. 08/580,102 by David T. Sheller, Steven
Edson and William A. Whittenberger; Ser. No. 08/577,615 by William
A. Whittenberger, David T. Sheller, and Gordon W. Brunson; Ser. No.
08/577,619 by David T. Sheller, William A. Whittenberger and Joseph
E. Kubsh; and Ser. No. 08/580,103 by William A. Whittenberger and
Gordon W. Brunson; The complete disclosure of all of these
applications are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to metallic catalytic converter
bodies, and, more particularly, to metal foil leaf assemblies and
converter bodies incorporating such assemblies.
2. Description of the Related Art
Catalytic converters containing a corrugated thin metal (stainless
steel) monolith typically have been formed of a plurality of thin
metal strips or foil leaves wound about a central pin or about
spaced "fixation" points. Such prior catalytic converters bodies,
have supported both the outer and inner end of the individual
layers by fixing them to the housing for the converter body and a
central pin or post. In certain instances, the interior support has
been provided by looping the foil leaves about a fixed point or
portion whereby the inner ends of the leaves have been supported by
other foil leaves. The thin metal strips or leaves forming the
multicellular honeycomb body also have been brazed together at
points intermediate the ends to form a rigid honeycomb monolith.
Various techniques such as soldering, welding, brazing, riveting,
clamping, reverse wrapping or folding, or the like, have been used
to secure the inner and outer ends, and usually the intermediate
portion, of the leaves or strips to the support member. While many
techniques have been used to assemble the leaves into the housing
and many leaf arrangements have been constructed, many arrangements
have been unable to survive severe automotive industry tests known
as the Hot Shake Test, the Hot Cycling Test, combinations of these
tests, cold vibration testing, water quench testing, and impact
testing.
The Hot Shake test involves oscillating (50 to 200 Hertz and 28 to
80 G inertial loading) the device in a vertical, radial or angular
attitude at a high temperature (between 800 and 1050 degrees C.;
1472 to 1922 degrees F., respectively) with exhaust gas from a gas
burner or a running internal combustion engine simultaneously
passing through the device. If the device telescopes, or displays
separation or folding over of the leading or upstream edges of the
foil leaves, or shows other mechanical deformation or breakage up
to a predetermined time, e.g., 5 to 200 hours, the device is said
to fail the test.
The Hot Cycling Test is run with exhaust flowing at 800 to 1050
degrees C.; (1472 to 1922 degrees F.) and cycled to 120 to 200
degrees C. once every 13 to 20 minutes for up to 300 hours.
Telescoping or separation of the leading edges of the thin metal
foil strips, or mechanical deformation, cracking or breakage is
considered a failure.
Also, the Hot Shake Test and the Hot Cycling Test are sometimes
combined, that is, the two tests are conducted simultaneously or
superimposed one on the other.
The Hot Shake Test and the Hot Cycling Test are hereinafter called
"Hot Tests." While they have proved very difficult to survive, the
structures of the present invention are designed to survive these
Hot Tests and other tests similar in nature and effect that are
known in the industry.
From the foregoing, it will be appreciated that catalytic converter
bodies and their method of manufacture have received considerable
attention, particularly by the automotive industry, are complex in
design and manufacture, and are in need of improvement.
SUMMARY OF THE INVENTION
The advantages and purpose of the invention will be set forth in
part in the description which follows, and in part will be obvious
from the description, or may be learned by practice of the
invention. The advantages and purpose of the invention will be
realized and attained by means of the elements and combinations
particularly pointed out in the appended claims.
To attain the advantages and in accordance with the purpose of the
invention, as embodied and broadly described herein, the invention
comprises a metal foil leaf assembly for catalytic converters, the
leaf assembly including at least two juxtaposed foil leaves, each
having opposite ends to establish a leaf length and at least one
corrugated leaf segment shorter than the leaf length. At least one
of the opposite ends is joined by appropriate means, such as a
weld, braze, or fold.
In another aspect, the advantages and purpose of the invention are
attained by a catalytic converter body comprising a cylindrical
jacket tube, and a plurality of radiating foil leaves having inner
and outer ends, the foil leaves extending in adjacent curved paths
and joined at the outer ends thereof to the jacket tube. The foil
leaves define fluid passage cells between juxtaposed flat and
corrugated leaf segments, and each of the foil leaves has at least
one corrugated segment.
In still another aspect, the advantages and purpose of the
invention are attained by a method of making a catalytic converter
body, comprising the steps forming an elongated strip of metal foil
having a series longitudinal segments coated with catalyst material
and transverse bands of uncoated flat metal foil between at least
some of the segments, the segments being alternately flat and
corrugated to provide fluid passage cells when flat and corrugated
segments are juxtaposed; folding each length to provide a leaf
element having juxtaposed coated segments and at least one end of
uncoated metal foil; and assembling a plurality of the leaf
elements to provide a converter body having a multiplicity of fluid
passage cells.
It is to be understood that both the foregoing general description
and the following detailed description are exemplary and
explanatory only and are not restrictive of the invention, as
claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute
a part of this specification, illustrate embodiments of the
invention and together with the description, serve to explain the
principles of the invention. In the drawings,
FIG. 1 is an isometric view depicting a continuous strip of foil
from which the leaf assemblies of the present invention may be
cut;
FIG. 2 is a side elevation illustrating an embodiment of the leaf
assembly of the present invention;
FIG. 3 is an alternative embodiment of a leaf assembly in
accordance with the invention;
FIG. 4 is a side elevation of a further leaf assembly embodiment of
the invention;
FIG. 5 is a schematic view illustrating a catalytic converter in
which various configurations of leaf assemblies of the invention
are shown;
FIG. 6 is an end view of a catalytic converter including the
plurality of leaf assemblies of the present invention;
FIG. 7 is an end view illustrating a star shaped assembly of the
leaf assemblies of the present invention;
FIG. 8 is an exploded view depicting the assembly of FIG. 7 with a
forming jig by which it is formed into a leaf assembly for a
catalytic converter;
FIG. 9 is an end view as seen on lines 9--9 of FIG. 8;
FIG. 10 is a cross-section on lines 10--10 of FIG. 8;
FIG. 11 is a cross-section on lines 11--11 of FIG. 8; and
FIG. 12 is a cross-section on lines 12--12 of FIG. 8.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference will now be made in detail to the present preferred
embodiments of the invention, examples of which are illustrated in
the accompanying drawings. Wherever possible, the same reference
numbers will be used throughout the drawings to refer to the same
or like parts.
The foil leaf arrangement may be constructed from "ferritic"
stainless steel such as that described in U.S. Pat. No. 4,414,023
to Aggen. One usable ferritic stainless steel alloy contains 20%
chromium, 5% aluminum, and from 0.002% to 0.05% of at least one
rare earth metal selected from cerium, lanthanum, neodymium,
yttrium, and praseodymium, or a mixture of two or more of such rare
earth metals, balance iron and trace steel making impurities. A
ferritic stainless steel is commercially available from Allegheny
Ludlum Steel Co. under the trademark "Alfa IV."
Another usable commercially available stainless steel metal alloy
is identified as Haynes 214 alloy. This alloy and other useful
nickeliferous alloys are described in U.S. Pat. No. 4,671,931 dated
9 Jun. 1987 to Herchenroeder et al. These alloys are characterized
by high resistance to oxidation and high temperatures. A specific
example contains 75% nickel, 16% chromium, 4.5% aluminum, 3% iron,
optionally trace amounts of one or more rare earth metals except
yttrium, 0.05% carbon, and steel making impurities. Haynes 230
alloy, also useful herein has a composition containing 22%
chromium, 14% tungsten, 2% molybdenum, 0.10% carbon, a trace amount
of lanthanum, balance nickel.
The ferritic stainless steels, and the Haynes alloys 214 and 230,
all of which are considered to be stainless steels, are examples of
high temperature resistive, oxidation resistant (or corrosion
resistant) metal alloys that are useful for use in making the foil
leaf core elements or leaves of the present invention, as well as
the multicellular honeycomb converter bodies thereof. Suitable
metal alloys must be able to withstand "high" temperature, e.g.,
from 900 degrees C. to 1200 degrees C. (1652 degrees F. to 2012
degrees F.) over prolonged periods.
Other high temperature resistive, oxidation resistant metal alloys
are known and may be used herein. For most applications, and
particularly automotive applications, these alloys are used as
"thin" metal sheets, referred to as foil, that is, having a
thickness of from about 0.001" to about 0.005", and preferably from
0.0015" to about 0.0037". The housings, or jacket tubes, hereof are
of stainless steel and have a thickness of from about 0.03" to
about 0.08", preferably, 0.04" to 0.06".
The multicellular converter bodies of the present invention
preferably are formed from foil leaves precoated before assembly,
such as described in U.S. Pat. No. 4,711,009 Cornelison et al. The
converter bodies of the invention may be made solely of corrugated
foil core elements which are non-nesting, or of alternating
corrugated and flat foil core elements, or of other arrangements
providing cells, flow passages, or a honeycomb structure when
assembled. In the preferred embodiments, the foil leaves, which
will be used as core elements, are precoated before assembly. The
ends are masked or cleansed to maintain them free of any coating so
as to facilitate brazing or welding to the housing or to an
intermediate sleeve.
As indicated in U.S. Pat. No. 4,911,007, supra, the coating is
desirably a refractory metal oxide, e.g., alumina, alumina/ceria,
titania, titania/alumina, silica, zirconia, etc., and if desired, a
catalyst may be supported on the refractory metal oxide coating.
For use in catalytic converters, the catalyst is normally a noble
metal, e.g., platinum, palladium, rhodium, ruthenium, indium, or a
mixture of two or more of such metals, e.g., platinum/rhodium. The
refractory metal oxide coating is generally applied in an amount
ranging from about 10 mgs/square inch to about 80 mgs/square
inch.
In some applications, corrugations preferably have an amplitude of
from about 0.01 inch to about 0.15 inch, and a pitch of from about
0.02 inch to about 0.25 inch. The amplitude and pitch of the
corrugations determine cell density, that is, the number of cells
per unit of cross-sectional area in the converter, body. Typically,
the cell density is expressed in cells per square inch (cpsi) and
may vary from about 50 cpsi to 2000 cpsi.
Where a non-nesting corrugated foil leaf core element is used, the
corrugations are generally patterned, e.g., a herringbone pattern
or a chevron pattern, or skewed pattern. In a "skewed pattern", the
corrugations are straight, but at an angle of from 3 degrees to
about 10 degrees to the parallel marginal edges of the strips. The
latter foil leaf core elements may be layered without nesting.
Where alternating corrugated and flat foil leaf core elements are
used in a non-nesting arrangement to form the multicellular bodies,
straight-through corrugations may be conveniently used, these
exhibiting the lowest pressure drop at high flow in fluid flowing
through the converter body. The straight-through corrugations are
usually oriented along a line normal to the longitudinal marginal
edges of the foil leaves, although, as indicated above, the
corrugations may be oriented along a line oblique to the
longitudinal marginal edges of the leaves.
To reduce stress, the "flat" foil leaf core elements preferably are
lightly corrugated to have corrugations with an amplitude of from
about 0.002" to about 0.01", e.g., 0.005" and a pitch of from about
0.02" to about 0.2", e.g., 0.1".
In accordance with the present invention, a layered metal sheet or
foil leaf assembly for catalytic converters is provided in which at
least two juxtaposed foil leaves, each having opposite ends to
establish a leaf length and at least one corrugated leaf segment
shorter than the leaf length, the juxtaposed foil leaves joined at
at least one of the opposite ends. The juxtaposed foil leaves may
be further joined to each other in at least one increment of length
between the opposite ends. However, for most applications, the
juxtaposed leaves are left unconnected between their ends to assure
flexure symmetry in adjacent leaves. Although the following
preferred embodiments provide a resulting body or assembly that can
be inserted into a cylindrical jacket, bodies of other shapes may
also be constructed according to the teachings of the present
invention.
Presently preferred embodiments of the invention are illustrated in
the drawings. In FIG. 1, a continuous strip of foil, designated
generally by the reference number 40, is shown to include
longitudinally spaced corrugated segments 42 spaced by flat
segments 44 of substantially the same length as the corrugated
segments of 42. The segments 42 and 44 are both coated with
catalytic material and thus represent active or working portions of
the foil. In the illustrated embodiment, a transverse band or short
segment 46 of uncoated foil is positioned between each corrugated
and flat segment. It is contemplated, however, that formation of
the strip 40 may be programmed so that the transverse bands are
formed at opposite ends of a series of the segments to be included
in a single foil leaf assembly. These bands of uncoated foil may be
effected by masking during the coating procedure or by removing
coating material after the strip 40 is formed. The foil strip 40
may range in width from 2 to 8 inches. Although the strip may
extend to any length in practice, the segments 42 and 44 are
preferably of an equal length in the range of from 3 inches to 8
inches. Additionally, the combined length of one flat segment 44
and one corrugated segment 42 represents one cycle of foil length,
as depicted in FIG. 1.
The strip 40 may be cut at the uncoated transverse bands 46 into
lengths to any multiple of a 1/2 cycle. The cut lengths may then be
juxtaposed, as shown in FIG. 2, so that the individual leaves
between the cut ends are complementary, that is the flat segments
44 on one leaf lie against corrugated segments 42 on the other and
vice versa.
The juxtaposed lengths of foil cut from the foil strip 40 and shown
in FIG. 2 represent a foil leaf assembly 48 including two leaf
elements or leaves 50 and 52 of a length determined by the distance
between the opposite ends 54 and 56 of each leaf. In this
embodiment, both ends of the two leaf elements are joined by welds
60, but it will be seen ensuing description of alternative
embodiments, that two juxtaposed leaves in a leaf assembly may be
joined at only one of such opposite ends.
Also as shown in FIG. 2, the two leaf elements are joined to each
other between opposite ends by an intermediate weld 62 connecting
overlying pairs of the transverse bands 46. If such intermediate
welds 62 are used between opposite ends of the leaf assembly, the
assembly is provided with additional strength, as a result of the
interconnected individual leaves, significantly in excess of the
strength of the same leaves left unconnected between their
ends.
From the assembly 48 shown in FIG. 2, it will be appreciated that
the two interconnected leaves 50 and 52 provide a plurality of
fluid passage cells 43 extending transversely of the assembly. In
addition, each leaf in the assembly contains at least one
corrugated segment 42 along the length thereof. As a result, a
measure of flexure is assured in each individual leaf along its
length by the presence of that at least one corrugated segment
42.
In FIG. 3, an alternative embodiment of the foil leaf assembly 48a
is shown in which the opposite ends of the leaf elements 50a and
52a are joined, but in this instance, by folds 54a and 56a of the
strip material 40 at an uncoated transverse band 46. Also in FIG.
3, it will be noted that the leaf elements 50a and 52a form pairs
of individual leaves joined at one end by the folds 54a, whereas
the folds 56a at the other end connect each pairs of leaf elements
50a and 52a.
In the embodiment of FIG. 3, the individual leaf elements represent
one cycle of the strip 40 described above with reference to FIG. 1.
In FIG. 4, a further alternative embodiment of a leaf assembly of
48b is shown in which the length of the leaf elements represent
11/2 cycles of the strip 40.
In the described embodiments, the complementing pairs of individual
leaf elements are "non-nesting" in that corrugated segments are
paired with flat segments to provide the fluid passage cells. Also,
the corrugations of the corrugated segments 42 are perpendicular to
the longitudinal direction of the strip 40, thus providing highly
efficient fluid flow passageways or cells.
In accordance with the present invention, the metal foil leaf
assembly described with reference FIGS. 1-4 is advantageously
incorporated in a catalytic converter body which the fluid passage
cell defining leaves are joined to and extend from a jacket tube to
a central inner region at which the inner ends of the leaves are
either unconnected or connected to a pliant central core section of
the converter body.
In FIGS. 5 and 6 of the drawings, a catalytic converter body is
shown in which the foil leaf assembly of the invention is embodied
in radiating layers extending in involute or spiral paths between a
peripheral jacket and an open central region. FIG. 5 is a largely
schematic illustration depicting spiral leaf assemblies 48c, 48d
and 48e of various cycle configurations in a converter body 70. In
particular, the leaf assembly 48c is configured of one foil cycle,
the leaf assembly 48d is 1.5 foil cycles, and the leaf assembly 48e
contains two foil cycles. All of the illustrated leaf assemblies
are of the same length.
In FIG. 6, a complete converter body 70a is shown. To form the
converter body 70a shown in FIG. 6, ends of the leaves at the outer
periphery of the converter body representing outer ends of each
leaf assembly 48 may be interconnected, either to each other as a
strip, or joined such as by welding or brazing to a separate
continuous foil strip from which the inner ends of the leaf
assemblies extend freely. The outer ends of the leaf assemblies are
then closed into a circle while the leaves are formed generally
into the spiral paths shown in the drawings. The closed strip of
leaf assemblies is then inserted into a cylindrical jacket and
brazed in place. The central region 72 of the converter body may
then be filled with a central core of a catalytic material defining
flow passageway cells.
In an alternative method, the inner ends of the foil assemblies 48
are connected to a sheet of foil with the outer ends of the
assemblies initially unconnected. The foil may be wrapped about a
core unit occupying the central region 72 and the assembly placed
in a cylindrical jacket. Again, the outer ends of the leaf
assemblies 48 may be brazed to the jacket tube.
In FIG. 7, a plurality of leaf pairs are initially assembled by
folding consecutive cycles of the foil strip 40 in the manner
depicted in FIG. 3 of the drawings. As described above with
reference to FIG. 3, each of the leaf elements shown in FIG. 7 is
joined at one end as a leaf pair by a fold 54a, and the respective
leaf pairs are joined their opposite ends by folds 56a. The leaf
pairs are formed into a circular array about the folds 56a and the
two cut ends of the strip 40 are joined at a weld 75 to form the
star shaped configuration of leaf assemblies 48 as shown in FIG.
7.
The star shaped assembly of leaves shown in FIG. 7 is subsequently
formed into a leaf assembly for a converter body to have the spiral
form configuration similar to that described with reference to FIG.
6. This shaping of the star form assembly of leaves is accomplished
by apparatus and method steps depicted in FIGS. 8-12 of the
drawings.
As depicted in FIG. 8, the star shaped assembly of leaves is
rotated 90.degree. from the plane of the figure and advanced
axially into a fixture 77 having internal radiating vanes 79 as
depicted in FIGS. 9-12. Thus, the radiating leaf assemblies of the
star shaped assembly will be received between the initially purely
radial vanes 79 as shown in FIG. 9. As the assembly is advanced
through the fixture, the diameter of the fixture gradually reduces
and the vanes 79 form the radiating leaves of the star shaped
assembly into gradually tightened spiral-form curves. As the star
shaped assembly exits the fixture, as shown in FIG. 12, it is
configured in spiral form paths similar to that shown in FIG. 6.
The formed leaf unit is then fed axially into a cylindrical body
jacket and brazed in place.
Other embodiments of the invention will be apparent to those
skilled in the art from consideration of the specification and
practice of the invention disclosed herein. It is intended that the
specification and examples be considered as exemplary only, with a
true scope and spirit of the invention being indicated by the
following claims.
* * * * *